Generally, various kinds of liquid crystal display have been developed. One common form of display is a light-influencing liquid crystal display. This type of liquid crystal display comprises a pair of substrates 2a and 2b, facing each other but not in contact with each other, as shown in FIG. 1. These substrates are usually formed of glass. The lower substrate 2a has a plurality of first light-transmissive pixel electrodes 3a formed thereon. The first light-transmissive pixel electrodes 3a may be formed by depositing light-transmissive conductive material such as indium tin oxide on the entire upper surface of the lower substrate 2a and then removing selected portions of the deposited material by utilizing a suitable mask and conventional photolithography techniques. An alignment layer 4a of polyimide is formed over the first light-transmissive pixel electrodes 3a and lower substrate 2a. In addition, a plurality of spacers 6 is formed on the alignment layer 4a. The alignment layer 4a and spacers 6 are formed by applying liquid alignment material containing inorganic material such as glass fiber and Al.sub.2 O.sub.3 onto the first light transmissive pixel electrodes 3a and lower substrate 2a by using a roller, as shown in FIG. 2A. The spacers 6 are embedded in the alignment layer 4a, creating a protrusion.
The alignment layer 4a and spacers 6 may also be formed in another way, as follows. First the alignment material is applied onto the first light-transmissive pixel electrodes 3a and lower substrate 2a by using a roller so as to form the alignment layer 4a. Then inorganic material such as Al.sub.2 O.sub.3 and glass fiber mixed with volatile or viscous liquid is scattered over the alignment layer 4a so as to make the spacers 6 attached to the alignment layer 4a, as shown in FIG. 2B.
Additionally, on the upper substrate 2b is deposited conductive light-transmissive material such as indium tin oxide that is patterned to form a common electrode or a second plurality of light-transmissive pixel electrodes 3b by utilizing a suitable mask and conventional photolithography techniques. Liquid alignment material of polyimide is applied to the upper substrate 2b with the second light-transmissive electrodes 3b by using a roller to form another alignment layer 4b.
After rubbing the entire surface of the lower substrate 2a having the first light transmissive pixel electrodes 3a, the first alignment layer 4 and the spacers 6 and rubbing the entire surface of the upper substrate having the second light-transmissive electrodes 3b and the second alignment layer 4b by using a soft cloth such as veludo, the upper and lower substrates 2a and 2b are printed with epoxy and then combined and scribed. Twisted nematic liquid crystal 5 is injected between the scribed substrates, which are then sealed. Thereafter, polarizing plates 1a and 1b are respectively attached to the outsides of the upper and lower substrates 2a and 2b with the offset angle of the incident light absorption axes being 0.degree.. If no electric field is applied to such a light-influencing liquid crystal display, it remains in a dark state because the molecules of the liquid crystal lie parallel with the substrates. On the contrary, when an electric field is applied to it, it transmits light because the molecules of the liquid crystal stand upright.
When forming the alignment layer 4a and spacers 6 by applying the mixture of liquid alignment material and spacers onto the lower substrate 2a with the first light-transmissive electrodes 3a, the spacers 6 are randomly scattered over the entire surface of the lower substrate 2a so that they may be positioned in the display regions or even cover the first light-transmissive pixel electrodes 3a. This causes the light rays entering through the polarizing plate 1a, lower substrate 2a and first light-transmissive pixel electrodes 3a to be scattered by the spacers 6 positioned in the display regions, thus considerably degrading the contrast. Further, the alignment layer 4a of organic material has a thickness not uniformly formed and also has pin holes owing to the surface tension and coalescing force between the alignment layer 4a and spacers 6. Moreover, the spacers 6 become often detached and broken during the rubbing so that the distance between the upper and lower substrates 2a and 2b may not remain uniform and the alignment layer 4a may be damaged, producing defects such as pin holes.
Meanwhile, when sequentially forming the alignment layer 4a and spacers 6, the spacers 6, mixed with volatile or viscous liquid, are randomly scattered over the lower substrate 2a with the first light-transmissive electrodes 3a, so that the spacers 6 may be placed in the display regions. This causes the light rays entering through the polarizing plate 1a, lower substrate 2a and first light-transmissive pixel electrodes 3a to be scattered by the spacers 6 positioned in the display regions, thus considerably degrading the contrast. In addition, since the vacuum adsorbing for removing dusts is performed prior to forming the alignment layer 4a, the dusts introduced during the formation of the alignment layer 4a and spacers 6 make the distance between the upper and lower substrates 2a and 2b not uniform.
As a result, in the light-influencing liquid crystal display produced according to conventional methods, the distance between the glass substrates is not uniform and the spacers are placed in the display regions, thus considerably degrading the contrast.